Cable data systems are used to allow cable TV subscribers to use the Hybrid-Fiber-Coax (HFC) network as a communication link between their home networks and the Internet. As a result, computer information (Internet Protocol packets) can be transmitted across the Hybrid-Fiber-Coax network between home computers and the Internet. The DOCSIS specification (defined by CableLabs) specifies the set of protocols that must be used to effect a data transfer across the Hybrid-Fiber-Coax network. Two fundamental pieces of equipment permit this data transfer: a cable modem (CM) which is positioned in the subscriber's home, and a Cable Modem Termination System (CMTS) which is positioned in the head end of the cable TV company.
In addition to data traffic, subscribers are more and more obtaining telephony voice services over networks other than the traditional public switched telephony network (“PSTN”). A multiple services operator (“MSO”) may provide such telephony services, in addition to data over cable service via DOCSIS. For example, CableLabs has established the PacketCable standard for providing telephony services over cable. A subscriber typically has a device that includes a DOCSIS cable modem for transmitting and receiving data and a media terminal adaptor (“MTA”) for processing voice traffic for transmission and reception over cable.
Subscribers from time to time may experience degraded service in the field due to packet loss and jitter. To evaluate and correct such degradation, equipment vendors may need to reproduce the jitter and packet loss conditions in a lab to facilitate determining and counteracting the cause of the degradation. However, standard network impairment test equipment is costly
Thus, there is need for a method and system for simulating network impairments for testing field scenarios on an MTA that is lest costly than purchasing and using standard network impairment equipment